The present invention relates to an apparatus which is used to electrostatically apply coating material to an object. More specifically, the present invention relates to control circuitry which monitors the operation of a power supply unit for an electrostatic spray gun.
Electrostatic spray guns have been used to apply either liquid or powder coating material to an object. The spray gun may include an electrode which creates an electric field which is effective to electrostatically charge particles of the coating material. A power supply unit converts a relatively low input voltage to a relatively high output voltage to charge the electrode. After extensive use of the spray gun, the power supply unit may fail due to many different causes, including failure of components of the power supply unit or break down of dielectric materials in the power supply unit.
During use of the spray gun, the failure of the power supply unit may be so gradual as to be imperceptible to an operator of the spray gun. This may result in a gradual degradation of the quality of coatings applied to a substantial number of objects before the operator realizes that the power supply unit is failing.